Intelligent Hearing Systems (IHS) proposes to develop a computerized device capable of simultaneously acquiring and processing otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs). A simultaneous OAE-AEP recording device will provide a needed tool for many clinical and research applications: l) differential diagnosis, 2) infant hearing screening and 3) intraoperative monitoring. The proposed system will acquire both OAEs and AEPs using the same set of stimuli and will implement advanced multi-modality (acoustic and electrical) artifact rejection techniques. In addition, the device will provide continuous acoustic monitoring of the stimulus during AEP acquisition, providing additional safeguards against erroneous results produced by occluded ear canals. The effects of new stimulus signals required for a dual OAE-AEP device will be investigated and compared to the standard derived nonlinear method (Kemp et al., 1986; I99Oa,b) currently used for transient OAEs (TEOAEs) and alternating and non-alternating polarity stimuli used for AEPs. A method of eliminating stimulus artifacts originating from non- alternating stimulus signals in both OAEs and AEPs is also proposed. This proposal will focus on TEOAEs during phase l. During phase Il it will be expanded to include distortion product OAEs and frequency following AEPs. PROPOSED COMMERCIAL APPLICATION: The proposed simultaneous OAE-AEP acquisition device will find an immediate commercial application for l) differential hearing diagnosis, 2) infant hearing screening and 3) intraoperative monitoring.